The present invention relates to hydraulic circuits for extension of cylinders, and more particularly relates to synchronized extension of horizontally-extending cylinders.
The U.S. Pat. Nos. 7,047,738, 7,134,280, and 7,322,190 disclose synchronized hydraulic systems that effectively control synchronized extension of multiple cylinders such as on a lift table. Further, the systems can be re-synchronized, air-purged, and refilled without disconnecting lines. However, improvements are desired to lower cost, and to improve simplicity and operation such as by removing the number of components and the expensiveness of those components.
Thus, an apparatus and method are desired having the aforementioned advantages and solving the aforementioned problems.